Two workers were injured Wednesday while repairing the inside of a sewage sludge dryer at the Milorganite fertilizer factory, Milwaukee Metropolitan Sewerage District officials said.

One of the workers was taken by ambulance to a local hospital for treatment of an injury, an MMSD spokesman said. None of the injuries are life-threatening but no other details were available. Steam Tube Rotary Dryer

There are 12 gas-fired dryers inside the Milorganite factory and all are shut down this week for annual maintenance.

Three contract employees were welding metal inside the 6-foot drum of one dryer when it unexpectedly turned on and started spinning, the spokesman said. The injuries occurred when the workers started tumbling inside the spinning drum. The gas turbine did not fire up.

No other dryers were turned on at the same time.

Federal investigators from the U.S. Occupational Safety and Health Administration were at Jones Island Wednesday afternoon to interview the workers and others on the possible cause of the incident and possible violations of workplace regulations.

Sand Removing Cyclone Veolia Water Milwaukee operates the Jones Island plant and Milorganite factory for MMSD and hired the maintenance contractor for the dryer repair.